The doctor will ask about your symptoms and your health and family history. A physical exam will be done. The doctor may be able to see that your thyroid is too large by looking at your neck.

Your doctor will do:

Blood tests —Blood tests measure the level of thyroid stimulating hormone (TSH) and antibodies. The diagnosis is made if the level of hormone is high and the levels of T4 are low. This means that the thyroid is not making enough hormone.

Thyroid antibodies may also point to autoimmune hypothyroidism, such as Hashimoto thyroiditis. It is not needed to make the diagnosis. It is the most common cause of hypothyroidism.

REFERENCES:

Hypothyroidism (underactive thyroid). National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/endocrine-diseases/hypothyroidism. Updated August 2016. Accessed May 20, 2019.

Hypothyroidism in adults. EBSCO DynaMed website. Available at:http://www.dynamed.com/topics/dmp~AN~T115914/Hypothyroidism-in-adults. Updated July 20, 2018. Accessed May 20, 2019.

Jonklaas J, Bianco AC, Bauer AJ, et al. Guidelines for the treatment of hypothyroidism. Thyroid. 2014 Dec;24(12):1670-751.

Last reviewed March 2019 by EBSCO Medical Review BoardJames P. Cornell, MD